Last obs before exposure flag and Baseline Flag

[KoulAshish]

Feature Idea

Hi All,

Starting from SDTMIG 3.3 a new variable --LOBXL (Last Observation Before Exposure Flag) has been added to finding domains with a view to replace --BLFL (Baseline Flag).

Should we tackle both together or is there a separate thread for --LOBXL.

Source: https://www.cdisc.org/standards/foundational/sdtmig/sdtmig-v3-3/html#Observations+and+Variables
Section: 4.5.9

Relevant Input

No response

Relevant Output

No response

Reproducible Example/Pseudo Code

No response

[MaguluriVenkata]

I suggest separating both, it's not necessary that both follow identical rule and also maintenance also is easy in future to have a dedicated space.

[rammprasad]

@rammprasad to complete the issue description.

[yli110-stat697]

@rammprasad to complete the issue description.

Hi @rammprasad can we define the desired input and output of the function?

[rammprasad]

Reference function - https://github.com/pharmaverse/roak_pilot/blob/main/R/oak_derive_blfl.R

[rammprasad]

@kamilsi - The function call in {sdtm.oak} can be oak_derive_blfl(ds_in, der_var, ref_var, ref_dat)

ref_dat will replace the code in the section below https://github.com/pharmaverse/roak_pilot/blob/main/R/oak_derive_blfl.R#L201 to https://github.com/pharmaverse/roak_pilot/blob/main/R/oak_derive_blfl.R#L210

The rest of the derivation logic is almost the same.